Besides its general mainline operations, United offers an ultra-luxurious P.S. Premium Service product on all non-stop flights between New York (JFK) and either Los Angeles or San Francisco. United's now defunct low cost Ted operation has been formally discontinued as of June 2008.
In the summer of 2008, United Airlines announced its new "Travel Options by United"1 program, which allows passengers to customize their travel by adding convenient services to their itinerary. Among these are Premier Access, providing fast track access through airport lines, and Baggage Delivery, where your bag is picked up from your arrival airport and sent to your final destination. More details can be found at united.com/traveloptions.

Houston George Bush Intercontinental Airport (IAH) is United's largest hub. It, along with United Express operate flights out of terminals A, B, C, and E. In addition to being United Airlines largest jumping off point to Latin America, United Airlines also offers several daily non-stop flights to a few destinations in Europe (mainly Amsterdam, Frankfurt, Munich, and London-Heathrow) and a flight to Tokyo-Narita, and Lagos. Other Star Alliance members such as Air Canada, Air China, Air New Zealand, All Nippon Airways, Avianca, EVA Air, Lufthansa, Singapore Airlines, and Turkish Airlines serve Houston as well and codeshare on many United flights.

Chicago O'Hare (ORD) provides a comprehensive selection of flights to destinations throughout Canada, the United States, Mexico, and the Caribbean, United Airlines offers several daily non-stop flights to Asia (Beijing, Hong Kong, Shanghai, Seoul, and Tokyo-Narita) and Europe (Amsterdam, Frankfurt, London-Heathrow, Munich, Paris-CDG), and many others. Sao Paulo, Brazil is served daily as well. Star Alliance partners offer United customers several additional options through codeshare operations. All mainline United flights depart from Terminal 1, where passengers can enjoy the spectacular lightshow in the famous underground tunnel that links Concourses B and C. Although some United Express flights operate from Terminal 1, most United Express passengers can expect to pass through the smaller and older Terminal 2. NOTE: Although most United Express flights actually utilize Terminal 2, all ticketing and baggage facilities are located in Terminal 1. All incoming international flights (except those from coming from pre-cleared Canadian, Irish, and Caribbean cities) will arrive in Terminal 5, requiring connecting passengers to disembark here, clear passport control and Customs, present themselves to an airline rep to re-check bags and then transfer back to Terminals 1 or 2 for their re-boarding procedures.

Denver (DEN) is a busy waypoint for passengers traveling across the United States, though virtually all flights are regional in nature. United does serve several cities in Canada, Hawaii, Panama, and Mexico from Denver; there is seasonal service during the summer to London-Heathrow as well. United operates exclusively from Concourse B, by far the largest and longest concourse at the airport. United Express passengers can enjoy the brand new regional wing of the concourse, having just opened to cater specifically to the rapidly growing regional jet and turboprop operations.

Guam (GUM) is a hub that services mainland Asia and connects to the U.S. mainland through Honolulu and Narita. United CEO and President, Jeff Smisek, said in 2012 that the Guam hub/service is a profitable operation for the airline. Previously, Guam was a hub for Continental was a wholly owned subsidiary under the company name Continental Micronesia. Guam is a U.S. territory and benefits from its proximity to mainland Asia and the rest of Oceania. Its main commerce is driven by Japanese tourism and the federal government, especially the U.S. military.

Los Angeles (LAX) is the smallest of United's six major hubs. Even so, Los Angeles is still a very common stopover for travelers flying to and from Hawaii and Australia. United offers non-stop service to London-Heathrow, Sydney, Melbourne and Tokyo-Narita. United Airlines operates the majority of its flights from Terminal 7 where it is equipped with customs halls for almost-exclusive use of United passengers. Some mainline flights and some international arrivals utilize Terminal 6, while United Express flights arrive and depart from Terminal 8.

San Francisco (SFO) is UA's major West Coast hub. Non-stop service is offered to Beijing, Frankfurt, Hong Kong, London-Heathrow, Osaka, Seoul, Shanghai, Sydney, Paris CDG and Tokyo-Narita. United operates domestic flights from Terminal 3's Boarding Area F, while international flights depart from the International Terminal's Boarding Area G. International arrivals use the International Terminal and deplane through side doors to the US CBP hall. Passengers need to re-check bags if making a connection and then clear security at the terminal of departure.

Washington Dulles (IAD) is one of UA's two major hubs on the East Coast. There are a plethora of feeder flights to the eastern states and Midwest and several transcontinental flights offered; however, this hub is most notable for handling many of United's transatlantic flights (Amsterdam, Brussels, Frankfurt, London-Heathrow, Munich, Paris-CDG, Rome, Dublin, Manchester, Geneva, and Zurich), as well as flight to Sao Paulo and, most recently, non-stop services to Kuwait, Bahrain, Tokyo, Dubai, Doha, Beijing, and San Salvador, Guatemala City, and San José, Costa Rica. United uses concourses A (for United Express), C and D (for select United Express and all United). Those arriving internationally go to the main terminal in mobile lounges from either the MFT or a hardstand. Other Star Alliance members serve this airport as well including Avianca, Copa Airlines, Lufthansa, Scandinavian Airlines, Turkish Airlines, Air China, All Nippon Airlines, South African Airways, and Ethiopian Airlines.

Newark Liberty Airport (EWR) is United's New York-Area hub. It's a jumping off point for direct flights to many destinations in Europe, Latin America, and Asia. In particular, it has direct routes to more European destinations than any of United's other hubs.

Tokyo-Narita(NRT) is United's Asian hub and the airport has international transfer facilities and domestic transfer belts.

United offers three-class service on international and JFK-LAX/SFO flights and two-class service on most domestic flights, including feeder flights on Canadair CRJ-700 and Embraer 170 regional jets. However, prop planes and the Canadair CRJ-200 and Embraer 145 only have economy class.

Uniquely among major US airlines, United sets apart the first few rows of economy class as Economy Plus, which has five extra inches of legroom. Economy Plus seating is given to ticketed economy passengers who:

hold elite status in the Mileage Plus program (see below); or

pay an additional fee at check-in or purchase, which varies based on the duration of the flight.

Economy Plus is available on most aircraft, including two-class commuter aircraft but not on one-class commuter aircraft (i.e. prop planes, CRJ-200s, and ERJ-145s).

747-400s are used on a few major intercontinental (mainly transpacific) routes. While first and business class on these planes is top-quality (flat beds in first class), the 777's economy class product is much better, as the 747s only have bulkhead video screens back. There is business class seating on the main deck and the upper deck: the upper deck seats are generally preferred, as the main deck seats form a ring around the galleys and upper deck access stairs, making this part of the cabin much more hectic than business class upstairs (or on the 777). However, recently, United has undergone an upgrade of its business and first class cabins with business class seats turning into "flat beds" and with Audio-Video on Demand in its top two classes. However, economy class did not change, although they'll install power outlets on United Economy 2014. This transformation has been completed on United's entire 747-400 fleet.

777-200s are used on most intercontinental routes, and have flat beds in first and business class. This plane has two configurations internationally, one with First, Business and Economy and the other with just Business and Economy. 91% of 777s (as of July 2013) have AVOD in all classes, however a few planes (mainly Intra-Asia flights out of Narita) have older cabins with multi-channel looping personal video in all three classes, and no lie-flat Business Class. Another version is used for flights to Hawaii and has only domestic first class and economy seating. The domestic version of the 777 does not offer personal video in either class of service - projection screens and overhead monitors are used.

767-300s are used on international routes which do not warrant 777 service. These aircraft have all been updated with United's International Premium Travel Experience (IPTE) featuring fully flat beds in business.In Economy, multi-channel looping video is available. Like the 777, there is also a two-class domestic version mainly used for flights to Hawaii. The domestic version of the 767 does not offer personal video in either class of service - projection screens and overhead monitors used.

757s are mainly used on medium-range and transcontinental flights, as well as international flights out of Newark. Most have two classes of service. However, if you are flying from New York JFK to Los Angeles or San Francisco, the 757s used on these routes have three-class premium service similar to what you would get on an international flight, with lie-flat seats (not beds) in first class and a roomy business class. This is to compete with American Airlines' nearly identical service which uses larger but older 767-200s.Flights to Europe on the 757 are equipped with AVOD in both classes (Business and Economy) and lie-flat beds in business.

787s are being added to the fleet to cover longer-range routes without the traffic to merit larger planes. They are configured with two classes of service, Business and Economy, with AVOD in both classes.

A320s and A319s are used on other medium-range flights, and may be swapped out for one another despite what your reservation or the timetable says. Many A320s are being reconfigured to feature leather seating in all classes.

MileagePlus members can earn miles when flying on any Star Alliance carrier, as well as Air One (Italy), Emirates (Dubai), Island Air (Hawaii), Qatar Airways, and TACA Airlines (Central America). All paid flights on United and United Express earn full mileage, while mileage accrual on partner airlines depends on the fare paid from zero to 100% of flight mileage. In addition, miles can be earned with a variety of travel, retail, and financial partners.

Miles can be redeemed for award flights on any of the airlines listed above, subject to availability. For itineraries exclusively involving flights on United or United Express, it is also possible to pay double the mileage to bypass capacity controls.

Miles can also be redeemed for single class of service upgrades on United or United Express, subject to availability and depending on the original fare paid. Mileage upgrades are not available on partner airlines, however; United has suspended its participation in the Star Alliance upgrade program indefinitely.

MileagePlus miles cannot be transferred into other programs, but can also be redeemed for hotel stays, car rentals, and some newspaper and magazine offerings.

Elite status is earned based on the number of Premier qualifying miles (PQMs) or Premier qualifying segments (PQSs) flown in a calendar year on United, United Express, or any other Star Alliance carrier (but not the other airline partners listed above). Elite flyers are given certain priority checkin, boarding, and standby privileges, as well as bonus miles, and the ability to accrue electronic certificates which provide class of service upgrades, among other benefits.

The Premier status levels are:

Premier Silver - 25,000 PQMs or 30 PQSs - Star Alliance Silver

Premier Gold - 50,000 PQMs or 60 PQSs - Star Alliance Gold

Premier Platinum - 75,000 PQMs or 90 PQSs - Star Alliance Gold

Premier 1K - 100,000 PQMs or 120 PQSs - Star Alliance Gold

In addition, United has created a somewhat mysterious "fifth tier" known as Global Services (GS). GS status is tied to revenue, instead of miles or flight segments flown, and is obtained by invitation only. GS members have priority over even 1Ks for upgrades and standby for flights, and are provided other special perks as well. However, as United does not publish the criteria used for invitation, or a comprehensive list of benefits, only anecdotal information about the program is available.

A Million Miler, one who has flown 1 million miles on United aircraft, receives Premier Gold status for life; at 2 million miles, Premier Platinum for life; at 3 million miles, 1K status for life; and at 4 million miles, Global Services for life.

United's main lounge network is called the United Club. The United Clubs offer light refreshments such as fruit and crackers, complimentary soft drinks and alcoholic beverages plus free WiFi. The United Clubs are open to paying United Club members as well as Star Alliance Gold members; United and US Airways Star Alliance Gold members are only granted access when on a same-day international itinerary on a Star Alliance carrier, however. One-time passes are available for $50.

Seven airports also have a United First International Lounge open to first class passengers on international itineraries (JFK, LAX, SFO, ORD, IAD, HKG, NRT), and three have an Arrivals by United Suite where international first and business class passengers arriving before noon can take a shower and eat breakfast (SFO, ORD, GRU). Outside the United States, the Star Alliance offers some additional lounges of these two types. These lounges are not open to elites by virtue of their elite status, and can only be accessed by passengers in those cabins.